Fastener unit



Feb. 4, 1936. G. E. PRENTICE FASTENER UNIT Filed Dec. 24, 1954 3 Sheets-Sheet 1 17222297120) fieoayeli neizfi Ze A W Q2?? Feb. 4, 1936. PRENTlCE 2,029,585

FASTENER UNIT Filed Dec. 24, 1934 5 Sheets-Sheet 2 Feb. 4, 1936. e. E. PRENTICE FASTENER UNIT Filed Dec. 24, 1934 3 Sheets-Sheet s enizc' a ZZZ Patented Feb. 4, 1936 UNITED STATES PATENT OFFICE FASTENER. UNIT George E. Prentice, Berlin, Conn.

Application December 24, 1934, Serial No. 758,973 2 Claims. (01. 24-205) This invention pertains to slide fasteners of the general type disclosed, for example, in the patent to Prentice No. 1,658,392, dated February 7, 1928, and relates more particularly to an improved fastener element or unit for use in such fasteners.

Fasteners of this type comprise opposed series of spaced fastener elements or units secured to and projecting outwardly from the edges of flexible supporting members or stringers,usually consisting of lengths of textile tape, each commonly provided with a head at the edge to which the fastener elements or units are secured. The units of the opposed series are moved into engaging interlocking relation by means of a manually actuable slider movable longitudinally of the series of fastener units and having appropriate guide channels for the respective series of units.

In the aforementioned Prentice patent there is described and claimed a highly desirable form of fastener unit, which for convenience may be referred to as a block type unit (thus distinguishing it from units formed by bending thin sheet material), such block type unit consisting of a solid block of metal punched or died out from fiat stock of substantially the same thickness as the completed unit. As described in said patent, the block or blank, when first cut from the stock, is of substantially symmetrical trapezoidal contour, having a deep recess in the wider of its parallel edges, thus defining a pair of spaced attaching legs or jaws adapted in a subsequent operation to be pressed toward each other and against opposite sides of the stringer tape, thereby to anchor the unit to the latter. The narrow end of the block is provided on one face (for example, the upper face) with a projecting locking pin, while the opposite (or lower) face has a corresponding depression or socket adapted to receive the locking pin of a unit of the opposed series. The outer end surface (at the narrow end of the block) is shown in the aforesaid patent as curved (substantially cylindrically) about a center approximately midway between the upper and lower faces of the unit, but the pin and the socket are set back from this cylindrically curved surface suificiently far so that they do not intersect or merge with said surface. While this curved end surface is desirable, it has not commonly been deemed essential. For example, when the units are to be secured to the tape as fast as they are punched or died out from the stock, (a procedure which affords no opportunity to round off this end, as by tumbling or other appropriate mechanical operation) this outer end surface is usually substantially flat and makes distinct angles with the upper and lower faces of the unit.

For some purposes it is desirable to provide a fastener of this general type which forms a. very tight closure, that is to say, one throu h which small discrete particles, for example tobacco, will not sift out or leak. With this object in view, I have experimented with an arrangement of fastener units disposed very closely together on the supporting stringer. Thus, I have made fastener 5 units from stock 0.040 inch thick, and have so spaced the units on the respective stringers that when assembled there are twenty-five such units per inch, thus forming a solid column of metal along that part of the fastener at which the units 10 of the opposed series overlap. This produces a fastener which, when held against the light, shows only a few crevices, and these of the most minute size.

While such a close and tight fastener is desirable, the interlocking of these closely spaced units is not quite so easy as when they are further apart, and if the units be of usual commercial type, the smooth interlocking and disengagement of the opposed series is not so readily accomplished, except by the employment of a special form of slider; or one having, for example, long and quite divergent cam surfaces,-an arrangement which necessitates the employment of a slider of undue size for some uses.

With the object, among other things of providing a fastener which will form a tight leakproof closure and which at the same time may be actuated smoothly and easily by means of a slider of small and commercially acceptable style and size, I have now devised an improved fastener unit of the block type of such shape that the units of one series are easily entered between those of the other, even when the units are closely spaced and without requiring that the units of the opposed series approach at so steep an angle as is necessary when usual types of unit are employed. Furthermore, I accomplish this desirable result without sacrifice of the extremely valuable features of the unit disclosed in the aforesaid 4O Prentice patent, to wit, the ability of the unit to withstand separating stress applied to the stringers when the opposed series are in interlocked relationship. Incidental to the improved result, the units are so shaped that when first brought into engagement, the units of the opposed series so interact that they cannot slip sidedise and cramp, as is often the case when ordinary units are actuated by a slider whose actuating cams are not steep enough or which has become worn or sprung. Moreover, the movement of the slider is much smoother and the closing and opening of the fastener is much easier than when units of usual commercial types are employed. As a further and unexpected resuit, I find that the use of such improved units makes it possible to close thefastener by downward movement of a slider of ordinary and usual type, when by accident the units of the opposite series have become separated below the slider.

In the accompanying drawings, wherein certain desirable embodiments of the invention have been disclosed by way of example,

Fig. 1 is a fragmentary front elevation, to large scale, of a fastener device embodying the present; invention;

Fig. 2 is a fragmentary front elevation, to larger scale, partly in section, omitting the flexible supports or stringers;

Fig. 3 is a side elevation of one of the improved fastener units, much enlarged;

Fig. 4 is a plan view of the unit of Fig. 3 illustrating the unit before application to the stringer;

Fig. 5 is a bottom plan view of the unit shown in Fig. 4;

Fig. 6 is a front end elevation of the improved unit;

Fig. 7 is a vertical sectionsubstantially on the line T--'l of Fig. 6;

Figs. 8 to 11 inclusive are fragmentary elevations illustrating the mode of approach and interengagement of my improved fastener units as the actuating slider is moved upwardly;

Figs. 12 to 15 inclusive are views similar to Figs. 8 to 11 but showing the mode of approach and interengagement of the improved fastener units by downward movement of an ordinary or usual slider when such units have become separated below the slider;

Fig. 16 is a fragmentary vertical section through a pair of complemental fastener units illustrating the guiding action of my improved unit; and

Fig. 17 is a section substantially on the line 11-41 of Fig. 16.

Referring to the drawings, the numerals I and 2 designate flexible stringers of any usual type having edges 3 and 4 respectively to which the opposed series 5 and 6 of fastener units or elements are attached. The edges of the stringers may be formed in any desired manner, for example as illustrated in the patent to Legat No. 1,934,865, dated November 14, 1933. The fastener comprises an actuating slider 1 of any desired kind, for example such as disclosed in the patent to Legat No. 1,969,270, dated April 7, 1934. The upward or fastener closing movement of the slider is limited by appropriate top end stops I and 2 The lower ends of the stringers are separably united by the bottom end stop comprising the members 8 and 9 secured to the respective stringers, the member 8 having a socket or loop memher I 0 which receives a hook element ll carried by the part 9.

In accordance with the present invention, the fastener comprises units of improved type which are so designed that as units of the opposed series approach, their contacting surfaces so engage as positively to prevent the units from slipping sidewise one on the other and constrain them to move substantially in the vertical planes of their respective stringers-as they converge into interlocking relationship.

Each unit, for example the units of the series 5, is punched or died from material of substantially the desired thickness of the completed unit. As originally formed, each unit is preferably of substantially symmetrical trapezoidal contour, as shown in Fig. 4, the wider end l2 of the unit, hereinafter for convenience referred to as the rear end, being provided with a deep recess I4, adapted to receive the edge of the stringer, such recess being interposed between the jaws or legs l5 and l 6 which, when pressed toward each other into the broken line position of Figs. 4 and 5,

firmly grip the edge of the stringer and anchor the unit thereto. The narrower or front end II of the unit is provided with an upstanding looking pin I1, preferably having a substantially flat vertical rear locking surface I8, and a flat top surface l9, more or less parallel with the top face of the unit, while the forward face 20 of the pin is preferably beveled or sloping. The under face of the unit is furnished with a recess 21 adapted to receive the pin II of a unit of the opposite series. Preferably, as illustrated in Figs. 4 and 5, the pin I1 and the recess 2| are elongate transversely of the unit, that is to say, their longer dimension is parallel to the end face l3,the latter also being fiat and elongate transversely, although the present invention is applicable to units having pins and sockets of other shapes and having the forward end of the unit relatively narrower than herein illustrated.

The socket 2| is set back slightly from the forward edge i 3 of the unit, being separated from the latter by a wall whose lower edge is furnished with a pin-guiding channel 22 leading rearwardly to the recess I 9. This channel 22 preferably has an arched or curved upper wall and is disposed with its deepest part substantially at the center of width of the unit. Preferably this channel 22 does not reach out to the lateral edges of the unit, but terminates short of such surfaces so as to leave guide elements 23 and 24 (Fig. 6) at opposite sides of the channel adapted to constrain the pin of a unit of the opposite series to move in the vertical plane of its stringer as it enters into interlocking engagement with the recess of the opposed unit. As noted from Figs. 16 and 17, the beveled face 20 of the pin acts more or less like the cam face of a latch, engaging the arched upper wall of channel 22 and leading the pin into the recess 2| where the flat face I! of the pin comes into latching or locking engagement with the inner fiat face of the inner wall of the recess. Thus the units are not able, when subjected to the lateral pressure required to interengage the opposed series, to move sidewise and cramp or tip, as often happens in the actuation of fasteners having units of ordinary type, when they do not approach each other at a steep angle, for example when it is endeavored to close the fastener by downward movement of the slider.

Referring to Figs. 8 to 11 inclusive, the operation of the improved fastener, when the slider I (here shown as of a usual type) is moved upwardly, is indicated diagrammatically. In Fig. 8 the units a and c of the right-hand stringer are within the slider l but have not yet been brought into contact with the units b and d of the opposed series. However, the unit e has just come into contact with the pin of the unit 1. In this position the upper part of the beveled surface of the pin of unit flies within the channel 22 of the unit e, and thus as these units continue to approach, they are held in proper relationship so that they cannot slip laterally. The units) and g are shown as having moved nearly into engagement, the flat top surface of the pin of the unit g now being within the channel of the unit I and being about to enter the socket of the latter unit. The unit 71 is shown as having its pin fully entered into the socket of the unit 9. In Fig. 9 the units c and d are shown as in substantially the same relative position as are the units f and g of Fig. 8, and in Figs. 10 and 11 the'fu'rther successive interengaging relations of these units may be followed, the units b and c in Fig. 11 being fully interlocked, while the units a and b are nearly interlocked.

Referring to Figs. 12 to 15 inclusive, the movement of the units of the opposed series by downward movement of a slider l of ordinary type is illustrated, such units having been separated accidentally below the slider. In Fig. 12, for example, the unit 17 is just contacting with the unit a, the guide channel 22 of the unit 12 receiving the beveled surface of the pin of the unit a. The pin of the unit b is advanced a little further into the channel of the unit c, while the pin of the unit is almost completely entered into the socket of the unit (1. The pin of the latter unit is fully seated in the socket of the unit e, but it may be noted that the units 1 and g are again beginning to retract from each other as the slider moves downwardly.

By the provision of the unit herein described, it is possible by downward movement of an ordinary slider, such as that indicated in Figs. 12 to 15, to cause the units of the opposed series to intermesh in a manner which is quite suggestive of the inter-meshing of the teeth of a pair of gears, the continued motion of the parts from the position of Fig. 12 being indicated in Figs. 12, 13, 14 and 15. Thus not only does the improved unit herein described permit of the making of a fastener whose units when interlocked are very close together, as shown in Figs. 1 and2, so as to form a substantially solid column of metal lengthwise of the fastener, but they also make the engagement of the fastener units by upward movement of the slider much smoother and easier, and further permit the units readily to reengage by downward movement of an ordinary slider when accidentally separated below it. As above noted, this latter effect appears to be due in part at least to the fact that the units are positively guided as they come into contact so that they cannot slip off sidewise and thus become cramped. It is probably due also in part to the fact that the channel at the forward end of each unit provides a certain clearance, thereby decreasing the effective thickness of the unit at its end, enabling the unit of the opposite series to slide endwise more readily than when the lower edge of the unit is not so recessed.

While the recess is preferably of the shape herein disclosed, I contemplate that it may be of other contour if desired, but in any event it is desirable that this recess be limited widthwise of the unit so as to furnish a definite guide for the pin of the unit of the opposite series, as distinguished from a mere beveling or curving of the lower corner of the unit. If the units are first cut from the stock and then, as a separate and independent operation, attached to the stringers, for example by delivering them from a magazine to the attaching devices, it is possible to subject them to an intermediate finishing process, for example to plate them with silver or other noncorrosive metal or material, thus permitting the use of a relatively cheap material for the body of the unit, while imparting a beautifully smooth and attractive surface finish.

For convenience in description I have herein employed such expressions as top face, bottom face, rear, front and sides of the unit, but have done so merely for ease in description and with reference to the illustration of the improved unit as it appears in the accompanying drawings, and without any intent thereby to limit the use of the improved unit to any particular position. Further, when I refer herein to a relative lateral movement of the units as undesirable, I intend to refer to such movement as, in the actual fastener, would cause the free ends of the units to swing forwardly or rearwardly out of line and out of the vertical planes of their respective stringers.

I claim: 1. A fastener of the class described having flexible stringers supporting opposed series of complemental fastener units, all of the units of both series being substantially alike, the units of the opposed series being so staggered and of such dimensions longitudinally of the fastener that when those of one series are interposed between those of the other series when the fastener is closed, the interposed parts collectively form a substantially solid column devoid of intervening crevices, each unit of each series consisting of a block of material having jaws at its rear end uniting it to its respective stringer, each unit having substantially parallel upper and lower surfaces and being of a transverse width at its front end greater than the distance between its upper and lower faces, each unit having a pin projecting upwardly from its upper face and a corresponding socket in its lower face, the pin and socket each being of greater dimension transversely than from front to rear but of less transverse dimension than the front end of the unit, each pin having an uninterrupted beveled front face extending substantially across its entire width, the socket of each unit being separated from the front face of the unit by a wall, each such wall having a pin guiding channel in its lower edge operative to receive the beveled face of the pin of a unit of the other series and to prevent relative lateral movement of the units as the latter move into interlocking position, each channel having an upper wall whose transverse contour substantially corresponds to that of the upper part of the pin. 2. A fastener unit for use in slide actuated fasteners of the kind in which flexible stringers support opposed series of like fastener units and wherein the units are of such dimensions longitudinally of the fastener that when the two series are united they collectively form a solid column at that part of the fasener at which the units overlap, each unit of each series being of blocklike form having substantially parallel upper and lower surfaces and having spaced jaws at its rear end for attaching it to its stringer, each unit being of substantial transverse width at its front end and having a pin of a slightly less transverse width projecting upwardly from its upper face adjacent to its free end and a corresponding socket in its lower face, the pin and socket each being of greater dimensions transversely than from front to rear, the pin having a substantially plain beveled front face extending across substantially its entire width, the socket being spaced from the front end surface of the unit by a wall having a pin guiding channel in its lower edge, said channel being located centrally of the wall and having an upwardly arched transverse contour substantially corresponding to that of the upper part of the pin and being operative by engagement with the beveled surface of the pin 01' a complementary unit to guide such pin into the socket.

GEORGE E. PRENTICE. 

